Add a cargo-semver-checks CI job to catch accidental breaking API changes

[Idaonoli]

Scope

With compliance-pausable intended as a publishable shared crate (see the crates.io publishing issue) and several contracts now exposing stable-ish client interfaces, add cargo-semver-checks to CI so an accidental breaking change to a public function signature is caught before merge rather than after a downstream consumer breaks.

Acceptance criteria

• A CI job runs cargo semver-checks against the previous published/tagged version for at least the pausable crate
• The job's scope (which crates it checks) is documented

[Sycosmile]

@Sycosmile has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hey! This one's well-scoped and I'm confident I can deliver a clean PR. Can I be assigned?

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[muizbolaji4]

@muizbolaji4 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello, I’d be happy to work on this issue. Please consider assigning it to me.

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[Joseph-tech10]

@Joseph-tech10 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I’d love to work on this because it’s the safety net that lets us ship faster without breaking downstream teams.

Why this issue

1. We’re about to publish compliance-pausable
Right now it’s internal. Once it hits http://crates.io, any accidental breaking change = every consumer’s CI goes red. With 8 contracts depending on shared primitives, a renamed function or removed trait blows up across the whole monorepo and any external integrators.

Catching that in CI instead of after release is the difference between "oops, fixed in 2 min" and "emergency patch + incident".

2. It’s cheap to add, expensive not to have
cargo-semver-checks compares your current branch to the last published version on http://crates.io. It knows what’s actually a breaking change per SemVer rules: removed pub fn, changed args, made trait non-object-safe, etc.

We don’t have to write tests for every API surface. The tool does it. That’s leverage.

3. Clear scope, immediate value
Target: at least compliance-pausable since it’s the first publishable crate. We can expand to the other 2 later.

How I’d implement it

.github/workflows/semver.yml
name: Semver Check

on:
pull_request:
paths:
- "contracts/compliance-pausable/**"
- ".github/workflows/semver.yml"

jobs:
semver:
name: cargo-semver-checks
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4
with:
fetch-depth: 0

  - uses: dtolnay/rust-toolchain@stable
  
  - name: Install cargo-semver-checks
    run: cargo install cargo-semver-checks
  
  - name: Check compliance-pausable
    run: cargo semver-checks check --package compliance-pausable --baseline-version auto

--baseline-version auto pulls the last published version from http://crates.io and diffs against it. No manual tagging needed.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Joseph-tech10 to this issue.

[miracle605]

@miracle605 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello team,
I'd like to take on this task and feel free to assign it to me.
Looking forward to getting started!

ℹ️ Repo Maintainers: To accept this application, review their application or assign @miracle605 to this issue.

[Neziahtech]

@Neziahtech has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

hello maintainer would love to solve this eta 14hours

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Neziahtech to this issue.

[drips-wave]

Congratulations, @miracle605! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @miracle605: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

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